Mugello 225 cylinder head hexagon nuts

Hi All, We have just been working on a Muggy 225 tonight. Had to rub the head of the barrel down to get to a squish of 1.45 but noticed we had a problem tightening up the 3 hexagonal bolts. It seems to me the threads are not long enough ??
Has anyone had this problem and knows the resolution, I would say the threads need to be another 10 mms longer, maybe even 15mm's as they were turning and not tightening up. The actual bolts are 57.4 mms long, of which 22.8 mms is the thread
Thanks
Has anyone had this problem and knows the resolution, I would say the threads need to be another 10 mms longer, maybe even 15mm's as they were turning and not tightening up. The actual bolts are 57.4 mms long, of which 22.8 mms is the thread
Thanks